2002/03/19 by V. NguyenKhac, NguyenKhac, V., K. NguyenVan +1
Mathematics · #46B20 #46E30 #Advanced Banach Space Theory #FOS: Mathematics #Functional Analysis (math.FA) #Metric Geometry (math.MG) #math.FA #math.MG #msc:46B20 #msc:46E30
paper · pdf · doi:10.48550/arxiv.math/0203190
10 pages, corrected some misprints
openalex publication_date 2002/03/19 · arxiv created 2002/08/18 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We give a characterization of extremal sets in Hilbert spaces that generalizes a classical theorem of H. W. E. Jung. We investigate also the behaviour of points near to the circumsphere of such a set with respect to the Kuratowski and Hausdorff measures of non-compactness.